The present invention generally relates to a pressure relief device for pressurized containers. Conventionally, pressurized containers such as aerosol cans are made with sufficient strength to withstand the pressure imposed upon them during the loading of the contents of the container. However, exposure of the container to excessive heat can increase the pressure within the container and cause the container to explode. Thus, there is a need for a pressure relief device which will automatically release unsafe excessive pressure from the container. Also, since most aerosol cans are disposable and not intended for reuse, the pressure relief device must have a low cost.
Various types of pressure relief valves have been provided in the prior art, none of which have been completely satisfactory. For example, safety vents through the product dispensing nozzle can become easily plugged due to the small orifice size and therefore are not adequately safe. Spring-type relief valves are costly to manufacture and assemble. Weakened rupture areas in the wall of the container are difficult to provide with precise tolerances, and once ruptured, the entire contents of the container are blown out and lost. Also, scoring of the internal finish of the container is unacceptable in many instances due to corrosion problems.
Accordingly, a primary objective of the present invention is the provision of a pressure relief device for pressurized containers which is economical to manufacture.
Another objective of the present invention is the provision of a pressure relief device which could be easily and economically mounted on aerosol cans.
A further objective of the present invention is the provision of a pressure relief device which is compatible with many types of materials.
Yet another objective of the present invention is the provision of a pressure relief device which can be easily manufactured to designed tolerances so as to have accurate and safe performance.
Another objective is the provision of a pressure relief device which re-seals itself after excessive pressure has been relieved from the container.
Still a further objective of the present invention is the provision of a pressure relief device which is tamper resistant.
These and other objectives will become apparent from the following description of the invention.